Fix NiceValueToThreadPriority failing on an unknown nice value.

base/threading/platform_thread_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stddef.h>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/platform_thread.h"
 #include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_POSIX)
 #include <sys/types.h>
 #include <unistd.h>
+#include "base/threading/platform_thread_internal_posix.h"
 #elif defined(OS_WIN)
 #include <windows.h>
 #endif
 
 namespace base {
 
 // Trivial tests that thread runs and doesn't crash on create and join ---------
 
 namespace {
 
@@ skipping 237 matching lines @@
     ASSERT_TRUE(PlatformThread::Create(0, &thread, &handle));
     thread.WaitForTerminationReady();
     ASSERT_TRUE(thread.IsRunning());
 
     thread.MarkForTermination();
     PlatformThread::Join(handle);
     ASSERT_FALSE(thread.IsRunning());
   }
 }
 
+#if defined(OS_LINUX)
+TEST(PlatformThreadTest, GetNiceValueToThreadPriority) {
+  using internal::NiceValueToThreadPriority;
+  EXPECT_EQ(ThreadPriority::BACKGROUND, NiceValueToThreadPriority(19));

[gab, 2016/04/08 15:52:51]

To make these cross-platform (well on OS_POSIX) you could extract the underlying
value from the map (it's okay to include the internal header in tests IMO),
would also make it clearer what's being tested IMO (e.g. NORMAL+1, etc.)

[Yuta Kitamura, 2016/04/12 10:19:00]

Yeah, updated the tests so they work on OS_POSIX.

+  EXPECT_EQ(ThreadPriority::BACKGROUND, NiceValueToThreadPriority(11));
+  EXPECT_EQ(ThreadPriority::BACKGROUND, NiceValueToThreadPriority(10));
+  EXPECT_EQ(ThreadPriority::BACKGROUND, NiceValueToThreadPriority(9));
+  EXPECT_EQ(ThreadPriority::BACKGROUND, NiceValueToThreadPriority(1));
+  EXPECT_EQ(ThreadPriority::NORMAL, NiceValueToThreadPriority(0));
+  EXPECT_EQ(ThreadPriority::NORMAL, NiceValueToThreadPriority(-7));
+  EXPECT_EQ(ThreadPriority::DISPLAY, NiceValueToThreadPriority(-8));
+  EXPECT_EQ(ThreadPriority::DISPLAY, NiceValueToThreadPriority(-9));
+  EXPECT_EQ(ThreadPriority::REALTIME_AUDIO, NiceValueToThreadPriority(-10));
+  EXPECT_EQ(ThreadPriority::REALTIME_AUDIO, NiceValueToThreadPriority(-20));
+}
+#endif
+
 }  // namespace base